StarCraft II:Heart of the Swarm is the second product in the StarCraft II trilogy featuring the zerg campaign and episode.

It will be released separately from the other two games, and is expected to be priced as an expansion. It follows StarCraft II: Wings of Liberty chronologically and storywise.

Heart of the Swarm is a sequel to Wings of Liberty. It focuses on Sarah Kerrigan and the development of a zerg empire. More will be seen of the Kel-Morian Combine and Umojan Protectorate. It will also have a separate ladder from Wings of Liberty.[/center]

kerrigan is turned human, why do the Zerg still follow her ?? And what happened to JImmy ??

I just hope they show us what the hell happened

I edited your post to add spoiler tags, just to be safe.

To answer your question...

Spoiler

If I understand it correctly, the Zerg Overmind (created by the Xel'Naga) knew about the coming darkness that will wipe out the Terrans, Protoss, and Zerg. You get to play that mission in the Wings of Liberty campaign ("In Utter Darkness"). Anyway, the Zerg Overmind knew about this darkness before Zeratul and what it did was create the Queen of Blades so that the Zerg may stand a chance against it. Obviously, the events of WoL changed things because Kerrigan was restored to her human form. Of course, that doesn't help things which explains the Heart of the Swarm campaign. You play as Kerrigan and work your way to becoming the Queen of Blades once again.

If I understand it correctly, the Zerg Overmind (created by the Xel'Naga) knew about the coming darkness that will wipe out the Terrans, Protoss, and Zerg. You get to play that mission in the Wings of Liberty campaign ("In Utter Darkness"). Anyway, the Zerg Overmind knew about this darkness before Zeratul and what it did was create the Queen of Blades so that the Zerg may stand a chance against it. Obviously, the events of WoL changed things because Kerrigan was restored to her human form. Of course, that doesn't help things which explains the Heart of the Swarm campaign. You play as Kerrigan and work your way to becoming the Queen of Blades once again.

Spoiler

From what one of the devs said in an interview yesterday or the day before, Kerrigan isn't going to become a Zerg again and that she's responsible for billions of deaths and would be horrified of that obviously. I don't know why she's trying to control the Zerg again, but she is certainly trying to control some portions of them, and she is obviously able to get certain psionic powers (among others) back again during the HotS campaign. Don't ask me how though lol